Generous summer bloom
WHILE you may have been dreaming, over the past few weeks, of the tropics and their hot colours, or of sweetly scented spring flowering bulbs, we are still in the depths of winter. When days are short and dark we all look for excuses, perhaps, to remain indoors, hibernating. A little exercise and engagement now, however, will ensure rewards in spring and summer. Pruning your hydrangeas will surely be on your list of winter chores.
You may have left the summer blooms of the easy-to-please hydrangea standing on tall stems to fade evocatively into burnished burgundies and blues. If so, it’s now time to cut back the stalks that flowered last summer.
Our grandmothers’ gardens could only boast of deep borders of mophead hydrangea, which were usually planted on the shaded, south side of the house. These days the genus is anything but dowdy as modern breeding has given us dozens of glamorous cultivars. The only difficulty is exercising restraint, for their impact is more dramatic if several of the one cultivar are planted en masse, quickly providing a voluminous effect.
First described in 1784 as Viburnum macrophylla, this generous bloomer was reclassified in 1830 as Hydrangea, part of the Hydrangeaceae family. The genus contains more than 70 species, native to China, Japan and areas around the Himalayas, which are most easily identified by their flowers. The most common are the mopheads, or Hydrangea macrophylla, which is then broken into several subspecies.
If your soil is acid the macrophyllas will flower blue; if alkaline, blooms will be pink. However the vast range of exciting new cultivars means that there is a colour for every garden. Among the newer varieties the white-flowering ‘Nymphe’ has frilled or serrated edges. Plant it as a rib through the garden, edged with, perhaps, the lowgrowing white Agapanthus ‘Snowball’.
The blooms of the very popular lacecaps, part of the macrophylla species, are in fact dozens of tiny fertile flowers surrounded by clusters of showy sepals. Among the most popular are the deep blue H. macrophylla ‘Blue Wave’ and ‘Beaute Vendomoise’, which unfurls a pretty pale green-to-pink and deepens to lilac.
The frost-hardy H. aspera var. villosa makes a big statement with its mauve lace cap flowers, and H. arborescens has limegreen mopheads. Its cultivar ‘Annabelle’ is a favourite due to its gorgeous emeraldgreen leaves and voluputous white flowers. It does best in cold climates, where it looks particularly smart edged with white freesias, white daylilies or low growing gardenias.
The deciduous oak-leaf hydrangea ( H. quercifolia) heralds the changing seasons with leaves that deepen to burgundy in autumn. In late spring and summer it flowers for weeks with white panicles. In a cool climate employ the climbing H. petiolaris to clothe a tree trunk or decorate a brick wall, or as a groundcover instead of the frost-tender Chinese star jasmine.
Hydrangeas look wonderful edging paths that wander through woodlands of viburnum, dogwood, maple and birch. You might foreground them with hellebores: the easiest to grow, Helleborus orientalis x hybridus, with its crushed-silk blooms that hang on for months past their winter peak, makes the perfect accompaniment.
The deciduous H. paniculata, from China and Japan, flowers in cream to pink cone-shaped panicles. You can see it in the photo above, blooming in the extraordinary gardens that cover Isola Bella, an island in Lake Maggiore, in the shadow of the Italian and Swiss Alps, owned since the 15th century by the Borromeo banking family and further testament to the plant-hunting obsession of many of the leading families of Europe and Britain. The gardens also demonstrate how effective mass plantings of the one species can be. Ah, to be so disciplined. PRUNING hydrangeas in late winter is simple. First remove any crossing, untidy or spindly limbs at the base of the plant. Then prune, to two sets of fat buds, the stems that flowered during the preceding summer. Propagate by taking sections with three sets of nodes from these prunings. Scape a little of the outer layer of tissue from the base of each cutting and plunge into a pot of propagating soil. Water, cover in plastic and leave in a warm but protected spot.
In less than a year you will have flowering pots to bring inside at Christmas, or to give as gifts. Or plant cuttings directly into the ground to beef up the borders.
I also prune as I pick the flowers in summer: hydrangeas last for days if plunged immediately into a deep vase or bucket of water. Blooms that have been left on the bush to fade and dry can be picked and sprayed for table decorations or wreaths. Follow daily garden tips and tricks on twitter.com/hollykerforsyth. Holly Kerr Forsyth’s new book, Seasons in My House and Garden, is out now.
Now is the time to prune those hydrangeas